Using zebrafish to define a novel role for AQP2 in kidney tubulogenesis

利用斑马鱼定义 AQP2 在肾小管发生中的新作用

基本信息

批准号：
7712503
负责人：
HUA A LU
金额：
$ 8.85万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-09-01 至 2011-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7712503
关键词：
Acute Kidney Failure Adhesions Adult Affect Animal Model Biological Biological Models Biological Process Biopsy Cell membrane Cells Cellular biology Cessation of life Complex Cyclic AMP Cyclic GMP Cyst Cystic kidney Cytoplasmic Vesicles Data Defect Development Diabetes Insipidus Diffusion Dimensions Dominant-Negative Mutation Embryo Epithelial Epithelial Cells Event Family Homeostasis Impairment In Vitro Kidney Kidney Failure Knock-in Mouse Life Light Lipids Liquid substance Lower Organism Maintenance Mammalian Cell Mediating Membrane Modeling Molecular Mus Mutation Names Neonatal Mortality Nephrogenic Diabetes Insipidus Organism Osmolar Concentration Pathway interactions Phosphorylation Plants Plasma Play Pronephric Duct Pronephric structure Proteins RGD (sequence)Recruitment Activity Regulation Research Role Signal Transduction System Tissues Transgenic Organisms Tubular formation Vasopressins Vertebrates Water Zebrafish angiogenesis animal data base cell motility cell type collecting tubule structure extracellular functional loss in vivo in vivo Model injury and repair insight knock-down lipid metabolism loss of function migration mouse model mutant neonate nephrogenesis novel overexpression public health relevance relating to nervous system response solute trafficking tubular necrosis urinary water channel

项目摘要

DESCRIPTION (provided by applicant): Water is transported through biological membranes by two pathways: lipid diffusion and water channel-mediated transport. Water channels, also named aquaporins, are present in many cell types and tissues, plants and lower organisms. AQP2 is one of this family. AQP2 is an important water channel present in principal cells of the mammalian kidney collecting duct to regulate water homeostasis. In addition to the on-going exciting research on AQP2 trafficking, there are emerging data from animals indicating that besides their classic role in water or small solute transport, aquaporins may exert additional roles in critical biological processes such as: neural signal transduction, cell migration and angiogenesis. Studies in a mouse knock-in model of AQP2 T126M, a mutation causing ER retention of AQP2, showed a urinary concentrating defect (nephrogenic diabetes insipidus, NDI), and unexpectedly, neonatal mortality from renal failure. Biopsy of homozygous mice revealed kidney tubular necrosis and cyst formation. This unusual finding prompts us to investigate a potential novel function of AQP2 in kidney development. Our preliminary study suggests that AQP2 indeed plays a role in epithelial cells migration and adhesion. Therefore, we propose that AQP2 plays a critical role in the development, maturation or maintenance of renal tubular integrity via its effects on epithelial migration, cell-cell and cell- matrix interaction. For these studies we will take advantage of the well-characterized zebrafish system to investigate these novel functions of AQP2 in vivo. Specifically, we will investigate spatial and temporal expression of an AQP2 orthologue in wild-type zebrafish and zebrafish with kidney cysts, and investigate any alteration of AQP2 trafficking under these conditions; 2) investigate roles of AQP2 in development/maturation of the pronephros in zebrafish by knocking down AQP2 function using morpholinos, and via tissue specific overexpressing of AQP2 with mutations that produce trafficking defects and migration defects in vitro. Our proposed studies will contribute not only to the understanding of the molecular mechanism underlying a novel function of AQP2, but also provide understanding of the unexpected contribution of a classic channel protein to other important aspects of epithelial cell biology. PUBLIC HEALTH RELEVANCE: Water channels, also named aquaporins, are present in many cell types and tissues, plants and lower organisms. They transport bulk water rapidly and provide a major pathway for transmembrane water transport. AQP2 is one of this family, and is an important water channel present in principal cells of the mammalian kidney to regulate water homeostasis.

描述（由申请人提供）：水通过生物膜通过两种途径运输：脂质扩散和水通道介导的运输。水通道，也称为水通道蛋白，存在于许多细胞类型和组织、植物和低等生物中。 AQP2 就是这个家族中的一员。 AQP2 是哺乳动物肾集合管主细胞中调节水稳态的重要水通道。除了正在进行的关于 AQP2 运输的令人兴奋的研究之外，来自动物的新数据表明，除了水通道蛋白在水或小分子溶质运输中的经典作用外，水通道蛋白还可能在关键的生物过程中发挥其他作用，例如：神经信号转导、细胞迁移和血管生成。 AQP2 T126M（一种导致 AQP2 ER 滞留的突变）的小鼠敲入模型研究显示，存在尿液浓缩缺陷（肾性尿崩症，NDI），并且意外地导致新生儿因肾衰竭而死亡。纯合小鼠的活检显示肾小管坏死和囊肿形成。这一不寻常的发现促使我们研究 AQP2 在肾脏发育中的潜在新功能。我们的初步研究表明AQP2确实在上皮细胞迁移和粘附中发挥作用。因此，我们认为AQP2通过其对上皮迁移、细胞-细胞和细胞-基质相互作用的影响在肾小管完整性的发育、成熟或维持中发挥关键作用。在这些研究中，我们将利用充分表征的斑马鱼系统来研究 AQP2 体内的这些新功能。具体来说，我们将研究野生型斑马鱼和肾囊肿斑马鱼中 AQP2 直系同源物的空间和时间表达，并研究这些条件下 AQP2 运输的任何变化； 2) 通过使用吗啡啉敲低 AQP2 功能，以及通过组织特异性过表达 AQP2 以及在体外产生运输缺陷和迁移缺陷的突变，研究 AQP2 在斑马鱼前肾发育/成熟中的作用。我们提出的研究不仅将有助于理解 AQP2 新功能的分子机制，而且还将提供对经典通道蛋白对上皮细胞生物学其他重要方面的意外贡献的理解。公共健康相关性：水通道，也称为水通道蛋白，存在于许多细胞类型和组织、植物和低等生物中。它们快速运输大量水，并提供跨膜水运输的主要途径。 AQP2 是该家族中的一员，是哺乳动物肾脏主细胞中调节水稳态的重要水通道。